Fluorinated cephalosporins

ABSTRACT

Cephalosporins having 2 or 3 fluorine atoms on the 3-methyl carbon are active antibiotics.

FLUORINATED CEPHALOSPORINS Inventors: George A. Boswell, Jr.; David R.

Brittelli, both of Wilmington, Del.

E. l. Du Pont de Nemours & Company, Wilmington, Del.

Filed: Dec. [1, 1972 Appl. No.: 314,024

Assignee:

US. Cl 260/243 C; 424/246; 260/239.l Int. Cl. C07D 501/20 Field of Search 260/243 C 1 NOV. 11, 1975 References Cited UNITED STATES PATENTS l2/l970 Essery 260/243 C 12/1972 Cooper H 260/243 C 12/1972 Murphy 260/243 c Primary E.mnziner-Nicholas S. Rizzo Attorney, Agent, or Firm-Anthony P. Mentis ABSTRACT Cephalosporins having 2 or 3 fluorine atoms on the B-methyl carbon are active antibiotics.

39 Claims, N0 Drawings FLUORINATED CEPHALOSPORINS BACKGROUND OF THE INVENTION modification of the cephalosporin molecule.

The cephalosporin C nucleus can be named as l-thia- 5-aza-6R-bicyclo[4,2,0 loctan-8-one, although cepham or cephem (for A or A -unsaturate) is simpler and easier to use for the compounds. The structure of cephalosporanic acid is 3-bromomethyl (prepared by B-methyl cephem)has been proposed in South African Pat. No. 6,900,761. Other recently issued patents such as Netherlands Pat. No. 7,004,479 and French Pat. No. 1,589,109 disclose 3- halomethyl derivatives where the halogen is specified as Cl, Br or 1. Recent West German Pat. No. 2,052,531 appears to disclose the monofluoro derivative but does not give any method or fluorine-containing reagents whereby such monofluoro derivative would be obtainable. It is widely recognized that properties and synthetic methods for preparing fluoro compounds are quite different than for the other halogens. No mention is made in the art of polyhalo derivatives, much less the difluoromethyl compound.

The cephalosporin ring system includes a fl-lactam ring fused to nitrogen of a thiazine ring system. Some of these ring systems are unstable to hydrolysis and fluori nation conditions. Furthermore polyhalogen derivatives are generally hydrolytically unstable and it is not surprising that in this field of antibiotic transformations no processes have been suggested for fluorination of cephalosporins.

DESCRIPTION OF THE INVENTION The invention embraces a fluorinated cephalosporin compound of the formula:

A halogen derivative, N-bromosuccinimide on LII wherein:

m is zero or l',

a and b are either a single or double bond with the proviso that b is a double bond only when m 0 and a is a single bond;

R is H or in which Q has up to 8 carbon atoms and is hydrocarbyl, amino-substituted hydrocarbyl or heterocyclic group;

R is H, hydrocarbyl of up to 13 carbon atoms or polychloro hydrocarbyl, alkali metal, alkaline earth metal, ammonium or amine salt; and

R is CI-IF CF or COF. It is to be understood that when a is a single bond and b is a double bond there is a hydrogen atom on each of the number 2 and 4 carbon atoms in the ring. When a is a double bond and b is a single bond there are two hydrogen atoms on the number 2 carbon atom.

The invention also includes pharmaceutically acceptable acid addition salts of the compounds, where for example, R is H. Such salts include the hydrochloride, sulfate, nitrate, phosphate, acetate, tartrate and citrate,

etc.

Specific examples of Q are 2-thienylmethyl, 3-[1,2,5- thiadiazolyl lmethyl, phenylmethyl 3- 2,5 ,6- tricyanopyrazinyllmethyl and furfurylmethyl. Examples of R are diphenylmethyl and 2,2,2-trichloroethyl as well as hydrogen, alkalii metal, e.g., sodium or potassium; alkaline earth, e.g., calcium; ammonium or amine salts, e.g., trimethylammonium, N-methylpiperidine, etc.

Particularly preferred are 3-ditluoromethylcephalosporins since these products are especially useful as antibacterials.

The new fluorine-containing cephalosporin derivatives are obtained by fluorination under anhydrous conditions of 3-oxygen-containing, including 3-aldehyde or 3-carboxy cephalosporins by a fluorinating reagent of the formula R SF where R is F, aryl or a diprimaryalkylamino group, the alkyls having up to 4 carbon atoms. The reaction is generally conducted under relatively mild conditions, e.g., from -80C. to +C., preferably 0 to 35C., whereby oxygen of the 3-oxy group is replaced by fluorine without substantial reaction with other oxygen groups in the cephalosporin. When the starting material contains a 3-aldehyde group the fluorination process yields a compound where R is CHF When the starting material contains a 3-carboxy group, the fluorination process yields a compound where R is CF When SE, is used as the fluorinating agent, some material is also produced where R is COF.

The diprimaryalkylaminosulfur trifluorides are known compounds. In general they are prepared by the reaction of a dialkylaminotrimethylsilane with sulfur tetrafluoride at a low temperature in an inert solvent, see Halasz et al., Chem. Ber. l03, 594-602 1970). Examples are dimethylaminosulfur trifluoride, diethylaminosulfur trifluoride, dipropylaminosulfur trifluoride and dibutylaminosulfur trifluoride.

The following sections show the sequence of steps useful in producing the compounds.

O 3 n s ]:N i F --u i? OOH SPECIFIC EMBODIMENTS OF THE INVENTION In the illustrative examples below all temperatures are in degrees Centigrade and all parts are by weight unless otherwise stated.

PART A Example I Al. Preparation of 3-Hydroxymethyl-7-( 2- thienylacetamido-3-cephem-4-carboxylic Acid (2).

o S x co H 0 mo H,C {If N moccn O I coon o I l "H S c N H,OH 0

OOH

This substance was prepared according to German Pat. No. 2,103,014. A suspension of 8.0 g of cephalothin (I) in ml H O was treated with 8.6 g K CO and the resulting solution was stirred at 36 for 4.25 hrs., then at 30 for 18 hrs. The resulting mixture was layered with 500 m! ethyl acetate and a solution of 10.0 ml conc. HCl in 50 m] H O was added. The ethyl acetate was dried (MgSO and removed in vacuo in yield 3.84 g (54%) of 3-hydroxymethyl7-( 2- thienylacetamido)-3-cephem-4-carboxylic acid, mp l38-l45d. Crystallization from ethyl acetate yielded material, mp l49-l5lD (lit. mp l5l.5l52d); ir (nujol mull): 3600-2400 (carboxyl OH), 3450 19 (amide N-H), 1790 (B-lactam C=O), 1745 (acid C=O). 1650 (amide C=O), and 1510 (amide 11 band) cm".

A2. Preparation of Benzhydryl 3Hydroxymethyl-7- (Z-thienylacetamido )-3-cephem-4-carboxylate 3).

II I 11H P r cii,cwj:( S

0 N) -H,0H

COOH

Using the procedure outlined in German Pat. No. 2,103,014, a solution of 3.84 g of the preceding acid in 150 ml of tetrahydrofuran was added to 2.6 g of diazodiphenylmethane. Gas evolution started immediately. The mixture was allowed to stir at 25 for 64 hrs, then stripped in vacuo and triturated with ether to yield 6.38 g of benzhydryl 3-hydroxymethyl-7-( 2- thienylacetamido)-3cephem-4-carboxylate, mp 116-138d (lit mp 169170d); ir (CHC1 3500 (OH), 1790 (B-lactam (3%), 1735 (ester C=O), 1670 (amide C=O), 1500 (amide 11 band), and 690 (monosubstituted benzene) cm mmr (dmso-d 8 3.22 (2, s, C -CH 3.92 (2, s, a-thienyl-CH 4.17 (1, s (broad), OH) 4.78 (2, s, C --CH 5.08 (1, d (J 5 Hz), C H), 5.77 (1, m, C -H), 6.88 (1, s, cHPh 6.92 (2, d (J 3 Hz), thiophene 3- and 5- W5), 7.31 (11, s (broad), aromatic and thiophene 4-H), and 9.01 (1, d (J =10 Hz), amide N-H).

Anal. Calcd. for C H N O S C, 62.31; H, 4.65 N, 5.38. Found: C, 62.50; H, 4.85; N, 5.33.

A3. Preparation of Benzhydryl 3 Formyl-7-(2- thieny1acetamido)- 3-cephem-4-carboxylate (4).

l I 1 1" S S CO CH Jones reagent CO,CH

As described in German Pat. No. 2,103,014, a solution of 3.3 g of benzhydryl 3-hydroxymethy1-7-(2- thienylacetamido)3-cephem-4-carboxylate (3) in ml acetone was cooled to 0 and 1.90 ml of 8N Q0 in H 50 (Jones reagent) was added in 0.10 ml increments over the period of 5.0 min. The resulting mixture was stirred for 40 min. at 0, then an additional 0.30 ml of oxidant was added. The mixture was stirred an additional 10 min, then poured into 450 ml satd. NaCl layered with 300 ml ethyl acetate. The organic layer was washed with water, dried (MgSO and stripped in vacuo. The resulting residue was chromatographed on silica with benzene, then 4:1 benzene ethyl acetate to yield 0.564 g of benzhydryl 3-formyl-7-( 2 thienylacetamido)-3-cephem-4-carboxylate; ir (CHCl 3400 (amide NH), 2720 (aldehyde H), 1810 (B-lactam C=O), and 1507 (amide 1! band) cm; uv max (C H OH): 298 mm (7750, 335 nm (7250), and 450 nm (620); nmr (CDCl;,); 8 3.17 and 3.90 (AB, 2 (J 19 Hz), C CH 3.95 (s, 2, athienyl CH 4.91 (D, 1 (J 5 H2), C H), 5.92 (dd, 1 (J 5 Hz, J 10 Hz), C H, 7.03 (s, 1, CO CHPh 7.31 (m, 13, phenyl & thiophene H), 6.78 (d, 1 (J =10 Hz), amide NH), and 9.60 (s, 1, aldehyde H).

A4. Preparation of Benzhydryl 3-Dif1uoromethyl-7- (Z-thienylacetamido)-3-cephem-4-carboxylate 5).

O l! 11H 5 CH-,CN 5 )ai I CO,CH

CHF

mixture of A A benzhydryl 3-difluoromethyl-7-(2- thienylacetamido)-cephem-4-carboxylates; ir (CHC1 3450 (amide N-H), 1820 (B-lactam C=O), 1750 (ester C=O), 1695 (amide C=O), and 1510 (amide 11 band) cm; F nmr (CHCl 8 116.43 (d (J 57 Hz), CHF (one of A A isomers)) and 115.82 (d(j 57 Hz), CHF (other isomer)), 3.74 (2, s, thienyl CH 4.94 (1, d(.] 6 Hz), C H), 5.91 (1, dd (J 6 Hz, J Hz), C 1 i), 6.72 (1, t (J 57 Hz), CHF and 7.3 (13, m, aryl +thiphene l-l); uv max (C H CH) 265 (7400).

Anal. Calcd. for C H N O S F C, 59.99; H, 4.10; N, 5.18. Found: C, 59.82; H, 3.94; N, 5.01

Example 2 A5. 3-Difluoromethyl-7-(2-thienylacetamido)-3- cephem-4-carboxylic Acid (23) u S U'CHICZ/I-N/QKHMH 0 l "H S E s l-cmcNjEf OCH To 0.190 g of benzhydryl 3-difluoromethyl-7-(2- thienylacetamido)-cephem-4-carboxylate (a mixture of A and A isomers) was added 0.25 ml of anisole and 1.0 ml of trifluoroacetic acid and the mixture was swirled at 27 for 5 min, then evaporated in vacuo. The residue was taken up in ethyl acetate and extracted with 5% NaHCO solution. The NaHCO solution was washed once with ethyl acetate, then brought to pH3 by the addition of dilute HCl and extracted with ethyl acetate. This ethyl acetate solution was dried (MgSO and evaporated in vacuo to yield 0.103 g (79%) of a 3:1 mixture of A :A 3-difluoromethyl-7-( 2- thienylacetamido)-cephem-4carboxylic acids, which was purified for analysis by crystallization from ethyl acetatepentane; ir (KBr pellet) 3650-2500 (carboxylOH), 1770 (B-lactam C=O), 1725 (carboxyl C=O), 1675 (amide C=O), and 1525 amode I1" band) cm' uv max (C H OH) 235 nm (10,500) and 265 nm (4900).

Anal. Calcd. for C H H O S F C, 44.91; H, 3.23; N, 7.43. Found: C, 44.61; H, 3.51; N, 7.23.

Example 3 A6. Preparation of Benzhydryl 3-Hydroxymethyl-7- (Z-thienylacetamido )-3 -cephem-4-carboxylatel -oxide CHCl,

To a solution of 16 g of crude hydroxy ester (obtained as in A2 above) in ml CHCl; at 0 was added dropwise a solution of 2.9 g of m-chloroperbenzoic (CHCg): 3550 (OH), 1795 (,B-lactam C=O), 1720 10 (ester C=O), 1660 (amide C=O), 1495 (amide ll band), and 1040 (sulfoxide) cm; nmr (dmso-d 8 3.68 (2, m, C 1;1), 3.82 (2, s, thienyl-CHz), 4.29 (2, d (J 5 Hz), C-3-CH OH), 4.86 (l, d (J 5 Hz),

As described in Belgian Patent 770,531, to a solution of 1.80 g (3.4 mmole) of benzhydryl 3-hydroxymethyl- 7-( 2-thienylacetamido 3-cephem-4-carboxylate- 1 oxide in 100 ml of acetone at was added over the s 8 (l, dd (J 5 Hz, J 8 Hz) 6.82 period of 2 min 0.90 ml of 8N CrO in H SO and the (1, 5, OQHPh 6.93 (2, d (J 3.0) Hz), thiophene 3- and 5-H), and 8.32 (11, m, phenyl and thiophene 4-l l).

Anal. Calcd. for C H N O S C, 60.45; H, 4.51; N,

mixture was stirred at 0 for 5 min, then poured into a mixture of 300 ml ethyl acetate and 300 ml of water and the ethyl acetate layer was washed with water, dried (MgSO and evaporated in vacuo. The residue 2 Found: C 60.32; H 4.62., N, was chromatographed on silica with CHCl to yield A7. Preparation of Benzhydryl 3-formyl-7-(2-thienyl-acetamido)-3cephem-4-carboxylate-1oxide (8).

[I ll 1.. S

S M ca -:1I O

0.716 g of benzhydryl 3-formyl-7-( 2- thienylac etamido)-3-cephem-4-carbo xylatel oxide after crystallization from methanol; uv max (C H OH): 269 nm (4600), 292 nm (4300), and 355 nm (1760);

Jones 5 nmr (dmso-d 3.75 and 4.32 (AB, 2 (J 19 Hz),

C -C ll 3.88 (s, 2, a-thienyl CH 5.08 (d, 1 (J 5 Hz), C -H), 6.18 (dd, 1 (J=5 Hz, J= 8.5 Hz), C H), 7.17 (1, s, COgCH P11 7.02 (d, 2 (J 3.0 Hz), thiophone 3- and 5-H), 7.44 (10, s, phenyl-H), 8.72 (d, 1 (J 8.5 Hz), amide N-H), and 9.85 (s, l, aldehyde-H).

A8. Benzhydryl 3-Difluoromethyl-7-( 2- thienylac etamido )-3-cephem-4-carboxylatel-oxide R l l cH,co-

R ca

R cur,

O SFS CH Cl,

To a solution of 0.498 g (2.1 mmoles) of phenylsulfur trifluoride in 20 ml of CH Cl at 25 under N is added dropwise with stirring a solution of 1.12 g (2.1 mmoles) of benzhydryl 3-formyl-7-( 2-thienylacetamido)-3- cephem-4-carb0xylatel-oxide in 20 ml of CH Cl The mixture is stirred at -25 for 0.5 hr. then poured into 100 ml of water and extracted with CH CI The CH Cl layer can be separated, dried (MgSO and evaporated in vacuo. Chromatography on silica gel with lzl cyclohexane/ethyl acetate gives benzhydryl 5 3-difluoromethyl-7-(2-thienylacetamido)-3-cephem-4- carboxylatel-oxide.

Example 4 A9. Benzhydryl thienylacetamido )-3-cephem-4-carboxyl ate O SnCl;

O N H,CN-[( S N HF OZCN i 2 The compound Q can alsobe made as follows: To a solution of 1.22 g (2.2 mmole) of benzhydryl 3- difluoromethyl-7-( Z-thienylacetamido )-3 -cephem-4- 26 carboxylate-l-oxide (2) in 10 ml CH CN and 3 ml DMF at 0 is added 0.455 g (2.4 mmole) anhydrous SnCl and 0.70 g (9.0 mmole) acetyl chloride and the resulting mixture stirred at 0 for 1.0 hr, then at 25 for 1.0 hr, and then poured into water and extracted with ethyl acetate. The ethyl acetate layer when washed with 3% HC] solution, 5% NaHCO solution, water, then dried (MgSO and stripped in vacuo gives the compound, which can be purified by the method out- 3-Difluoromethyl-7-(2- lined in A4 above.

Example 5 A10. Benzhydryl 7-Amino-3-difluoromethyl-3-cephem-4-carboxylate p-toluenesulfonic acid salt (l This salt can be made as follows: A solution of 1.65 g (3.2 mmole) of benzhydryl 3-dilfuoromethyl-7-( 2- thienylacetamido)-3-cephem-4-carboxylate in 35 ml CCh is cooled to below 25 in a 200 ml-3-necked round bottom flask fitted with thermometer and mechanical stirrer and under N Then 0.70 ml of N-ethyl morpholine is added and the mixture was stirred at 25 while a suspension of 0.7g of PCI in 15 ml of dry CCL, is added over the period of 25 min. through a solid addition adapter. The resulting mixture is stirred at for 30 min., then cooled to below 25 again and treated with 0.70 ml of N-ethyl morpholine in 25 ml of dry methanol. This solution is stirred at 0 for 2 hrs and then poured into 50 ml of H 0 in a separatory funnel and the pH adjusted to just over 7 (just lime green to pH paper) by the addition of cone. NaOH solution. After shaking, the CCL, layer is separated, dried (MgSO and added to a solution of 0.56 g of p-toluenesulfonic acid hydrate in 15 ml of ethyl acetate. The resulting solution when allowed to stand in a cold room for a few days gives a crystalline p-toluenesulfonic acid salt a benzhydryl 7-amino-3-difluoromethyl-3-cephem- 4-carboxylate.

Example 6 Al l. Benzhydryl 7-Amino-3-difluoromethyl-3-cephem-4-carboxylate (ll).

s cu -Q 0," mwl-Q/ N (HF2 4 lol Example 7 A12. Benzhydryl 3-Difluoromethyl-7-(3-[2,5,6- tricyanopyrazinyl]acetamido)-3-cephem-4-carboxylate (12.).

0 NC N CN I NC N Ii c N CH in S NC N cincN The residue from procedure 11 above can be dissolved in 50 ml acetone and 1.05 g of urea is added. When a solution of 1.37 g of 3-(2,5,6- tricyanopyraziny1)acetyl chloride in 25 ml acetone is added and the mixture was stirred at 25 for 1.0 hr, on silica with CHCl gives benzhydryl 3-difluoromethyl-7 (3-[ 2 ,5 ,6-tricyanopyraziny1]-acetamido )-3-cephem-4- carboxylate.

Example 8 A13. 3-Difluoromethy1-7-(3[2,5,6- tricyanopyrazinyl]-acetamido)-3-cephem-4-carboxylic Acid 13 m R NC N C N I L r NC N i H,-- R H R cm" NC N C N I 0 2.5192 1. N c N CRAP-d N CH F,

13 2 NC N C N H N C CHQME-K N 0 HF:

The benzhydryl ester can be removed as follows: To 0.797 g (1.3 moles) of benzhydryl 3-difluoromethyl- 7-( 3-[ 2,5 ,-tricyanopyrazinyl ]acetamido )-3-cephem- 4-carboxylate and 0.150 g of anisole at 0 is added m] of trifluoroacetic acid and the mixture stirred at 0 for 1.0 hours. Then the mixture is evaporated in vacuo, dissolved in ethyl acetate, washed with water, the ethyl acetate solution dried (MgSO,) and stripped in vacuo. The residue can be recrystallized from ethanolic ethyl acetate to give 3-difluoromethyl-7( 3- 2,5 ,6- tricyanopyrazinyllacetamido)-3-cephem-4-carboxylic acid.

Example 9 A14. Preparation of 2,2,2-Trichloroethyl 6-Phenylacetamidopenicillanate L5) 0 0 H PhCH,C-N clcocmccl,

NV c0014 I 14 acetone 5 H PhCH,CN

(IO,CH,CC13

In the manner described in J. Org. Chem, 36, 1264 (1971), a mixture of g of penicillin G potassium salt, (13) 100 ml of dry acetone, and 27 g of pyridine cooled to 0 in an ice bath was added to a solution of 48 g of 2,2,2-trich1oroethyl chloroformate in 300 ml of acetone and the mixture was stirred at 0 for 18 hrs. The mixture was then filtered and the filtrate was heated to 40, and the warm filtrate was diluted with water until cloudy. The resulting solution was put in the cold room overnight, then filtered to yield 80 g after drying overnight in a vacuum dessicator. The filtrate was diluted with an equal volume of water and chilled overnight. This yielded 15 g, for a total of g (95%) of 2,2,2-trichloroethyl 6-phenylacetamidopenicillanate, mp 159161(1it mp l60161); ir (CHC1 3400 (amide N-H) 1790-1770 (broad, B-lactam and ester C=Os), 1680 (amide C=O) and 1500 (amide II") cm; nmr (CDCl;,): 8 1.52 (6H, s. C( Hs)2), 3.63 (2H, s, benzyl- Clj 4.52 (1H, s, 4-l' i). 4.78 (2H, s, Cl l CCl 5.67

(2H, m, 6- and 7-H), 6.40 (1H, d (.l=8), Nlj), and 7.34 (H, s, aromatic) Al5. Preparation of 2,2,2-Trichloroethyl 6- 1 Phenylacetamidopenicillanate-l-oxide (L6). 5 PhCH,CN

N CH,

C l COCH2CCIE O 10 L? 5 com 1 A solution of 9.64 g of 2,2,2-trichloroethyl 6- N phenylacetamido-penicillanate-l-oxide, 0.45 g of 87% phosphoric acid, and 0.32 g of pyridine in 200 ml of dry dioxane was heated under reflux for 16 hrs. The flask OzCHiCC,a was under a Soxhlet apparatus and condenser containing 15 g of molecular sieves in the extraction thimble to L5 dry the distillate before it was returned to the reaction 20 flask. After the heating period was completed, the solvent was evaporated on a rotary evaporator using a vacuum pump. The residue was dissolved in 200 ml of methylene chloride and washed with 100 ml each of water, 2111 HQ solution, water, 3% NaHCO solution,

N and water (saturated NaCl solution was added to the aqueous phase to break up any emulsions which formed during these extractions). The resulting methylene chloride solution was dried over anhydrous MgSO filtered, and evaporated on a rotary evapora- L. 39 tor. The residue was triturated with 25 ml of ethanol.

After crystallization was complete, the solid was filtered, yielding 3.8 g (41%) of 2,2,2-trichloroethyl 7- Following the procedure described in J. Org. Chem, phenylasetamgdof3methyl'2'cepllenl4'carboxylatei 36, 1264 1971 m 25 g of 2,2,2-trichloroethyl 6- P #50461 mp 162 464 1r (CHCMI 3400 phenylacetamidopenicillanate in 265 ml of chloroform (amde 1785 (B- aCtam C='O), l745 (ester cooled to 0 was added dropwise a solution of l 1.66 g 1695 (amlde C=0) and 1500 band) of m-chloroperbenzoic acid in 130 ml of chloroform. ("Tl-13 fl 5 H 5, 1's

The resulting solution was stirred at 0 for 2 hrs, then H2 benzyl B2) m,

washed with 5% NaHCO solution, dried over anh 40 -CH CCl 6.64 (1H, d (J 4.5 Hz), 6-H), 5.83 (1H,

drous MgSO filtered, and evaporated to dryness on a doublet of double HZ, J 9 -11) rotary evaporator. The resulting residue was triturated d 9 amlde and 730 s,

with ether and filtered. Isolated was a total of 25.2 g l- (99%) f ZQ L -i hI eth I 6. A17. Preparation of 2,2,2-Trichloroethyl 7- phenylacetamidopenicillanate-l-oxide, mp l67-l69 45 y i -m yl-3- eph m-4- ar xyl -1- (lit mp l67-l69); ir (CHCl3); 3400 (amide NH), Oxide (L3)- 1805 (B-lactam C=O), 1770 (ester C=O), 1695 (amide C=O), I500 (amide II band), and 1050 (sulfoxide) H PhcH C cm"; nmr (CDCl;,): 8 L27 (s, 3H, B-2-C];l 1.73 (s, Cl 3H, a-Z-Clj 3.57 (2H, s, benzyl -CH 4.73 (2H, m, -Clj CCl 4.98 (IH, d (J 5 Hz), 6-H), 5.89 0 OH (1H, doublet of doublets (J 5H2, 1' 10 Hz), 7-H), 5 3 6.90 (1H, d (J 10 Hz), amide N-H), and 7.26 (5H, PhCH,CN singlet, aromatic). N

Al6. Preparation of 2,2,2-Trichloroethyl 7- Phenylacetamido-3-methyl-3-cephem-4-carboxylate 3 CO,CH,CCL

O g agar o i H l 5 PhCHgCN N pyridine h Hz N o,cu.cc1,

To a solution of 2.32 g of ester 17 in 25 ml Cl-lCl at was added a solution of 1.1 g of m-chloroperbenzoic acid in ml of CHCl and the mixture was stirred at 0 for 2.0 hrs. The mixture was then washed with 5% NaHCO dried (MgSO and stripped in vacuo. Trituration of the residue with ether followed by filtration yielded 2.6 g of 2,2,2-trichlor0ethyl 7- phenylacetamido-3-methyl-3-cephem-4-carboxylate- I oxide, mp l94l95.5 d; ir (CHCl 3500 (amide NH), 1810 (B-lactam C=O), 1760 (ester C 0), 1700 (amide (i=0), 1500 (amide II" band), and 1040 (sulfoxide) cm Anal. Calcd. for C, H,,C1 N 0 S: C, 45.00; H, 3.55; N, 5.83. Found: C, 44.92; H, 3.43; N, 5.52.

A18. Preparation of 2,2,2Trichloroethyl 3- Bromomethyl 7-phenylacetamido-3-cephem-4-carboxylate-l-oxide (19) O i o N Q CHE/ CO,CH:CC|;,

o i Q '3 CH cN o CH,Br

CO CH CCI In the manner described in German Patent 2,042,169, a degassed solution of 5.0 g (0.010 mmoles) of sulfoxide 18 and 2.8 g of N-bromosuccinimide in 400 ml of ethylenedichloride at 0 under N was irradiated at 0 for 1.0 hour with a 100 w. medium pressure Hanovia mercury lamp. The mixture was then washed with 2100 ml portions of water and the combined aqueous layers were washed with 50 ml of ethylene dichloride. The combined ethylene dichloride solutions were dried (MgSO stripped in vacuo, and the residue was chromatographed on silica gel with 9:1 Cfl Cl -acetone, yielding 2.53 g (43%) of 2,2,2-trichloroethyl 3-bromornethyl-7-phenylacetamido-3- cephem-4-carboxylate-1-oxide, mp l60163d (lit mp 162164 d); nmr (dmso-d 8 3.40 and 3.87 (AB, 2 (J 14 Hz), C l-is), 3.36 and 4.04 (AB, 2, J 19 Hz), thienyl (oz-CH 4.39 and 4.76 (AB, 2 (J 11 Hz), C -CH -Br), 5.00 (d, 1 (J 5), C H), 4.93 and 5.35 (AB, 2 (J 13), Cl-I CCl 5.90 (dd, 1 (J =5Hz, J= 8 Hz), C l-l), 7.25 (s, 5, phenyl- H), and 8.25 (d, 2 (J 8H2) amide N-H).

A19. 2, 2,2-Trichloroethyl 3-l-lydroxymethyl-7- phenylaceta mido- 3-cephem-4-carboxylatel-oxide 9) i 5 1:1 benzene- H DMSO CH T CH,Br

C0 CH,CCl

O Q IL. H,CN

CH,0H

O CH CCl Jones Reagent CHgOH CO CH CCI To a solution of 0.843 g (1.7 mmole) of 2,2,2-trichloroethyl 3-hydroxymethyl-7-phenylacetamido-3- cephem-4-carboxylate-l-oxide in 50 m1 of acetone at 0 is added over the period of about 2 min. 0.450 ml of 8N CrO in H and the mixture is stirred at 0 for 5 min, then poured into a mixture of 300 ml ethyl acetate 300 ml water and the ethyl acetate layer washed with water, dried (MgSO and evaporated in vacuo. The residue when chromatographed on silica gel with CHCl gives 2,2,2-trichloroethyl 3-formyl-7- phenylacetamido-3-cephem-4-carboxylatel -oxide.

A21. 2,2,2-Trichloroethyl 3-Difluoromethyl-7- phenylacetamido-3-cephem-4-carboxylatel-oxide (2;).

O SF

CH=CN o 1 cmci 9 To a solution of 0.494 g (1.0 mmoles) of 2,2,2-trichloroethyl 3-forrnyl-7 -phenylacetamido-3-cephem-4- carboxylate-l-oxide in an 80 ml l-lastelloy bomb in ml of CH Cl at is added 0.324 (3.0 mmoles) of sulfur tetrafluoride, and the mixture rocked at 25 for 1.0 hr, then poured into 50 ml of ice water and extracted with CH CL The CH Cl layer is separated, dried (MgSO,), and evaporated in vacuo. Chromatog raphy on silica gel with chloroform gives 2,2,2-trichloroethyl 3-formyl 7-phenylacetamido-3-cephem-4- carboxylatel -oxide.

cop-1 cm,

CH CN N 0 CHF,

CinCN CHF co ciccl To a solution of 1.03 g (2.0 mmole) of 2,2,2-tri chloroethyl 3-difluoromethyl7-phenylacetamido-3- cephem-4carboxylate-l-oxide in 10 ml CH CN and 3 ml DMF at 0 is added 0.414 g (2.2 mmole) anhydrous SnCl and 0.700 g (9 mmole) acetyl chloride, and the resulting mixture is stirred at 0 for 1.0 hr, then at 25 for 1.0 hour, and then poured into water and extracted with ethyl acetate. The ethyl acetate layer after washing with 3% HCl solution, 5% NaHCO solution, and water, and then drying (M gSO,) and stripping in vacuo gives 2,2,2-trichloroethyl 3-difluoromethyl-7- phenylacetamido-3-cephem-4-carboxylate which can be purified by chromatography on silica gel with chloroform.

EXAMPLE 1 1 A23. 3-Difluoromethyl-7-phenylacetamido-3-cephem-4-carboxylic Acid (25) CH COOl-l coon This can be prepared as follows: To 0.750 g (1.5 mmoles) of 2,2,2-trichloroethyl 3-difluoromethyl-7- phenylacetamido-i -cephem-4-carboxylate in 15 ml of glacial acetic acid at 0 is added 0.975 g (l5 mmole) zinc dust and the mixture stirred at 0 for 3.0 hours. Then the mixture is poured into ml of water, extracted with ethyl acetate, and the ethyl acetate solution is dried (MgSO and stripped in vacuo. The residue can be recrystallized from 50% ethanol to give 3- difluoromethyl-7-phenylacetamido-3-cephem-4-carboxylic acid.

EXAMPLE 12 A24. B-Acetoxymethyl-7-(2-thienylacetamido)-3- cephem-4-carboxylic Acid (25) s l! llH CH CN O S N ll H OCCH O C Na 0 U u-cmc i Q S N H 02c" 0 ls 313 s o 2 s L |\J n N moccu, 0

COOH

0 H u H S HQCN s l N moccn, O

coon

Using the method outlined in German Offenlegungschrift 2,103,014, 20.4 g of 3-acetoxymethyl-7-( 2- thienylacetamido)-3-cephem-4-carboxylic acid was dissolved in 60 ml of dry pyridine, with heating and then 6 m1 of acetic anhydride was added to the cooled solution. The mixture solidified on standing for 2 hours. It was then diluted with 50 ml of pyridine and the solid filtered and washed with 150 ml of ethyl acetate. The product was recrystallized from 150 ml of ethyl acetate and 20 ml of alcohol to yield 15.4 g of 3-acetoxymethyl-7-(Z-thienyIacetamido)-2-cephem-4-carboxylic acid pyridine salt, mp 150151D.

1 (Guise A26. 3-Acetoxymeth y1-7-( 2-thienylacetamido)-2- cephem-4-carboxy1ic acid (2]) l l H CH 5 0 5 51 2 l: n

N moccn, o i COOH 25) H H S ma 0 s II N mocca, O

l l I I C This compound was prepared according to German Ofienlegungschrift 2,103,014 as follows: To 13.8 g of the pyridine salt in 500 ml of water layered with ethyl acetate was added 6N HCl until pH4 was reached. Then the acid was extracted into the ethyl acetate layer which was dried (MgSO and evaporated to yield 1 1.2 g of 3-acetoxymethyl-7-(2-thienylacetamido)-2-cephem-4-carboxylic acid, mp 149-154.

A27. 3-Hydroxymethyl7-(2-thienylacetamido)-2- cephem-4-carboxylic acid u H 5 H C l C") NaOl-l H,OCCH

N o 1 COOH O I! n H 5 H CN I 5 1; N J'- H (IOOH 23;

This compound was prepared according to German Offenlegungschrift 2,103,014 as follows: A suspension of 11.8 g of the acetoxymethyl compound 10 in 150 ml of water and 15 ml of acetone was treated with 21 ml of H11 NaOl-l and heated to 40". Then the mixture was kept at 50 for 17 hours, then layered with 500 ml ethyl acetate and acidified to pH4 with 2-lj H 80 The product was extracted with the ethyl acetate layer, which was washed with water, dried (MgSO and concentrated at 35 in vacuo. From this concentrate, 3.0 g of 3-hydroxymethyl 7-(2-thieny1acetamido)-2- cephem-4-carboxylic acid, mp 147149d, was obtained A28. Benzhydryl 3-l-lydroxymethyl-7-( 2- thienylacetamido)-2-cephem-4-carboxylate (2?) 

1. A COMPOUND OF THE FORMULA
 2. A PHARMACEUTICALLY ACCEPTABLE ACID ADDITION SALT OF (1).
 2. a pharmaceutically acceptable acid addition salt of (1).
 2. A compound according to claim 1 in which R2 is CHF2.
 3. A compound according to claim 1 in which R2 is CF3.
 4. A compound according to claim 1 in which R2 is COF.
 5. A compound according to claim 1 in which R is 2-thienylacetyl.
 6. A compound according to claim 1 in which R is 2,5,6-tricyanopyrazinylacetyl.
 7. A compound according to claim 1 in which R is phenylacetyl.
 8. A compound according to claim 1 in which R is H.
 9. A compound according to claim 1 in which R1 is H.
 10. A compound according to claim 1 in which R1 is benzhydryl.
 11. A compound according to claim 1 in which R1 is 2,2,2-trichloroethyl.
 12. A compound according to claim 2 which is benzhydryl-3-difluoromethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylate.
 13. A compound according to claim 2 which is 3-difluoromethyl-7-(2-thienylacetamido)-3-cepHem-4-carboxylic acid.
 14. A compound according to claim 2 which is benzhydryl-3-difluoromethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylate-1 -oxide.
 15. A compound according to claim 2 which is benzhydryl-7-amino-3-difluoromethyl-3-cephem-4-carboxylate.
 16. A compound according to claim 2 which is benzyhydryl-3-difluoromethyl-7-(3-(2,5,6-tricyanopyrazinyl)-acetamido)-3 -cephem-4-carboxylate.
 17. A compound according to claim 2 which is 3-difluoromethyl-7-(3-(2,5,6-tricyanopyrazinyl)acetamido)-3-cephem-4 -carboxylic acid.
 18. A compound according to claim 2 which is 2,2,2-trichloroethyl-3-difluoromethyl-7-phenylacetamido-3-cephem-4 -carboxylate-1-oxide.
 19. A compound according to claim 2 which is 2,2,2-trichloroethyl-3-difluoromethyl-7-phenylacetamido-3-cephem-4 -carboxylate.
 20. A compound according to claim 2 which is 3-difluoromethyl-7-phenylacetamido-3-cephem-4-carboxylic acid.
 21. A compound according to claim 3 which is benzhydryl-3-trifluoromethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylate.
 22. A compound according to claim 3 which is 3-trifluoromethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylic acid.
 23. A compound according to claim 3 which is benzhydryl-3-trifluoromethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylate-1-oxide.
 24. A compound according to claim 3 which is benzhydryl-7-amino-3-trifluoromethyl-3-cephem-4-carboxylate.
 25. A compound according to claim 3 which is 2,2,2-trichloroethyl-3-trifluoromethyl-7-phenylacetamido-3-cephem-4 -carboxylate.
 26. A compound according to claim 3 which is 3-trifluoromethyl-7-phenylacetamido-3-cephem-4-carboxylic acid.
 27. A process comprising contacting under anhydrous conditions a compound of the formula
 28. A process comprising contacting a compound of the formula
 29. The process of claim 27 in which m
 0. 30. The process of claim 27 in which m
 1. 31. The process of claim 27 in which m 0 and R4 is
 32. The process of claim 27 in which m 0 and R4 is -CH2CCl3.
 33. The process of claim 27 in which the fluorinating agent is SF4.
 34. The process of claim 27 in which the fluorinating agent is phenylsulfur trifluoride.
 35. The process of claim 28 in which m
 0. 36. The process of claim 28 in which m
 1. 37. The process of claim 28 in which m 0 and R4 is
 38. The process of claim 28 in which m 0 and R4 is -CH2CCl3.
 39. A process which comprises the sequential steps of a. contacting at a temperature range of about 30*-65*C. a compound of the formula 